Hcfo-containing polyurethane foam-forming compositions, related foams and methods for their production

ABSTRACT

Polyurethane foam-forming compositions, methods of producing polyurethane foams, polyurethane foams produced from such compositions made by such methods, as well as isocyanate-reactive compositions. The polyurethane foam-forming compositions include a polyol blend, a blowing agent composition, and a polyisocyanate. The polyol blend includes an aromatic amine-initiated polyether polyol, a saccharide-initiated polyether polyol, and an aromatic polyester polyol and has a content of —C 2 H 4 O— units of 3 to 6% by weight, based on the total weight of the polyurethane foam-forming composition. The blowing agent composition includes a hydrochlorofluoroolefin and a carbon dioxide-generating chemical blowing agent.

FIELD

This specification pertains generally to hydrochlorofluoroolefin(“HCFO”)-containing isocyanate-reactive compositions, polyurethanefoam-forming compositions, and polyurethane foams produced therefrom.

BACKGROUND

Rigid polyurethane foams are used in numerous applications. They areproduced by reacting a polyisocyanate and an isocyanate-reactivecompound, usually a polyol, in the presence of a blowing agent. One useof such foams is as a thermal insulation medium in the construction ofrefrigerated storage devices, including refrigerated appliances andtractor trailers. The thermal insulating properties of closed-cell rigidfoams are dependent upon a number of factors, including the average cellsize and the thermal conductivity of the contents of the cells.

The thermal conductivity of the contents of the cells depends upon theblowing agent(s) used. Fluorocarbons have historically often been usedbecause of their low thermal conductivity. However, fluorocarbons,including chlorofluorocarbons (“CFCs”), hydrofluorocarbons (“HFCs”) andhydrochlorofluorocarbons (“HCFCs”), are greenhouse gases that have beenphased out of use. Halogenated olefins, such as HCFOs, areenvironmentally-friendlier alternatives for such fluorocarbons, but theycan be costly.

Thermal efficiency, often evaluated with respect to a low thermalconductivity, or “K-factor”, is an important feature of rigidpolyurethane foam insulation. Even seemingly small reductions inK-factor, such as on the order of just a few percent, can translate intovery significant reductions in energy usage and cost over the lifetimeof the device in which the foam is used. For example, according to someestimates, a 2% decrease in K-factor can result in approximately a 1%improvement in energy performance for a refrigerator, which can allowfor using a smaller compressor, thus providing potential energy and costsavings over the life of the refrigerator. Alternatively, the thicknessof the refrigerator wall or door could be reduced while achievingsimilar insulation properties, thus allowing for increased internalstorage space.

As a result, HCFO-blown rigid polyurethane foams that have improvedthermal conductivity, while at the same time using less HCFO, andmaintaining favorable foam physical properties and processingcharacteristics, would be highly desirable.

SUMMARY

In certain respects, this specification relates to polyurethanefoam-forming compositions. These polyurethane foam-forming compositionscomprise a polyol blend, a blowing agent composition, and apolyisocyanate. The polyol blend comprises: at least 30% by weight,based on total weight of the polyol blend, of an aromaticamine-initiated polyether polyol having a functionality of at least 2.5and an OH number of 200 to 600 mg KOH/g; at least 30% by weight, basedon total weight of the polyol blend, of a saccharide-initiated polyetherpolyol having a functionality of 4 to 6 and an OH number of 200 to 600g/KOH gram; and 1 to 25% by weight, based on total weight of the polyolblend, of an aromatic polyester polyol having a functionality of 1.5 to3 and an OH number of 150 to 410 mg KOH/g. The sum of the amount of thearomatic amine-initiated polyether polyol, the saccharide-initiatedpolyether polyol, and the aromatic polyester polyol is at least 90% byweight, based on the total weight of the polyol blend, and the polyolblend has a content of —C₂H₄O— units of 3 to 6% by weight, based on thetotal weight of the polyurethane foam-forming composition. The blowingagent composition comprises (1) a physical blowing agent and (2) acarbon dioxide-generating chemical blowing agent. The physical blowingagent comprises a hydrochlorofluoroolefin, wherein thehydrochlorofluoroolefin is present (i) in an amount of 5% to 15% byweight, based on total weight of the polyurethane foam-formingcomposition, and (ii) in an amount of at least 80% by weight, based ontotal weight of physical blowing agent in the blowing agent composition.The polyisocyanate is present in an amount sufficient to provide anisocyanate index of 1.15 to less than 1.40.

In other respects, this specification relates to methods of producing apolyurethane foam. The methods comprise reacting, at an isocyanate indexof 1.15 to less than 1.40, a polyurethane foam-forming compositioncomprising a polyol blend, a polyisocyanate, and a blowing agentcomposition. In these methods, the polyol blend comprises at least 30%by weight, based on total weight of the polyol blend, of an aromaticamine-initiated polyether polyol having a functionality of at least 2.5and an OH number of 200 to 600 mg KOH/g; at least 30% by weight, basedon total weight of the polyol blend, of a saccharide-initiated polyetherpolyol having a functionality of 4 to 6 and an OH number of 200 to 600g/KOH gram; and 1 to 25% by weight, based on total weight of the polyolblend, of an aromatic polyester polyol having a functionality of 1.5 to3 and an OH number of 150 to 410 mg KOH/g. The sum of the amount of thearomatic amine-initiated polyether polyol, the saccharide-initiatedpolyether polyol, and the aromatic polyester polyol is at least 90% byweight, based on the total weight of the polyol blend, and the polyolblend has a content of —C₂H₄O— units of 3 to 6% by weight, based on thetotal weight of the polyurethane foam-forming composition. The blowingagent composition comprises (1) a physical blowing agent and (2) acarbon dioxide-generating chemical blowing agent. The physical blowingagent comprises a hydrochlorofluoroolefin, wherein thehydrochlorofluoroolefin is present (i) in an amount of 5% to 15% byweight, based on total weight of the polyurethane foam-formingcomposition, and (ii) in an amount of at least 80% by weight, based ontotal weight of physical blowing agent in the blowing agent composition.

In yet other respects, this specification relates to isocyanate-reactivecompositions. These isocyanate-reactive compositions comprise a polyolblend and a physical blowing agent compositions. The polyol blendcomprises at least 30% by weight, based on total weight of the polyolblend, of an aromatic amine-initiated polyether polyol having afunctionality of at least 2.5 and an OH number of 200 to 600 mg KOH/g;at least 30% by weight, based on total weight of the polyol blend, of asaccharide-initiated polyether polyol having a functionality of 4 to 6and an OH number of 200 to 600 g/KOH gram; and 1 to 25% by weight, basedon total weight of the polyol blend, of an aromatic polyester polyolhaving a functionality of 1.5 to 3 and an OH number of 150 to 410 mgKOH/g. The sum of the amount of the aromatic amine-initiated polyetherpolyol, the saccharide-initiated polyether polyol, and the aromaticpolyester polyol is at least 90% by weight, based on the total weight ofthe polyol blend, and the polyol blend has a content of —C₂H₄O— units of5 to 15% by weight, based on the total weight of the isocyanate-reactivecomposition. The blowing agent composition comprises (1) a physicalblowing agent and (2) a carbon dioxide-generating chemical blowingagent. The physical blowing agent comprises a hydrochlorofluoroolefin,wherein the hydrochlorofluoroolefin is present (i) in an amount of 10%to 30% by weight, based on total weight of the isocyanate-reactivecomposition, and (ii) in an amount of at least 80% by weight, based ontotal weight of physical blowing agent in the blowing agent composition.

This specification is also directed to rigid polyurethane foams producedfrom such foam-forming compositions and by such methods, as well as tocomposite articles comprising such rigid foams and panel insulation thatincludes such rigid foams.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a graph of the rise rate pressure profiles of some of theExample foams.

DETAILED DESCRIPTION

Various implementations are described and illustrated in thisspecification to provide an overall understanding of the structure,function, properties, and use of the disclosed inventions. It isunderstood that the various implementations described and illustrated inthis specification are non-limiting and non-exhaustive. Thus, theinvention is not limited by the description of the various non-limitingand non-exhaustive implementations disclosed in this specification. Thefeatures and characteristics described in connection with variousimplementations may be combined with the features and characteristics ofother implementations. Such modifications and variations are intended tobe included within the scope of this specification. As such, the claimsmay be amended to recite any features or characteristics expressly orinherently described in, or otherwise expressly or inherently supportedby, this specification. Further, Applicant(s) reserve the right to amendthe claims to affirmatively disclaim features or characteristics thatmay be present in the prior art. Therefore, any such amendments complywith the requirements of 35 U.S.C. § 112 and 35 U.S.C. § 132(a). Thevarious implementations disclosed and described in this specificationcan comprise, consist of, or consist essentially of the features andcharacteristics as variously described herein.

Any patent, publication, or other disclosure material identified hereinis incorporated by reference into this specification in its entiretyunless otherwise indicated, but only to the extent that the incorporatedmaterial does not conflict with existing definitions, statements, orother disclosure material expressly set forth in this specification. Assuch, and to the extent necessary, the express disclosure as set forthin this specification supersedes any conflicting material incorporatedby reference herein. Any material, or portion thereof, that is said tobe incorporated by reference into this specification, but whichconflicts with existing definitions, statements, or other disclosurematerial set forth herein, is only incorporated to the extent that noconflict arises between that incorporated material and the existingdisclosure material. Applicant(s) reserves the right to amend thisspecification to expressly recite any subject matter, or portionthereof, incorporated by reference herein.

In this specification, other than where otherwise indicated, allnumerical parameters are to be understood as being prefaced and modifiedin all instances by the term “about”, in which the numerical parameterspossess the inherent variability characteristic of the underlyingmeasurement techniques used to determine the numerical value of theparameter. At the very least, and not as an attempt to limit theapplication of the doctrine of equivalents to the scope of the claims,each numerical parameter described in the present description should atleast be construed in light of the number of reported significant digitsand by applying ordinary rounding techniques.

Also, any numerical range recited in this specification is intended toinclude all sub-ranges of the same numerical precision subsumed withinthe recited range. For example, a range of “1.0 to 10.0” is intended toinclude all sub-ranges between (and including) the recited minimum valueof 1.0 and the recited maximum value of 10.0, that is, having a minimumvalue equal to or greater than 1.0 and a maximum value equal to or lessthan 10.0, such as, for example, 2.4 to 7.6. Any maximum numericallimitation recited in this specification is intended to include alllower numerical limitations subsumed therein and any minimum numericallimitation recited in this specification is intended to include allhigher numerical limitations subsumed therein. Accordingly, Applicant(s)reserves the right to amend this specification, including the claims, toexpressly recite any sub-range subsumed within the ranges expresslyrecited herein. All such ranges are intended to be inherently describedin this specification such that amending to expressly recite any suchsub-ranges would comply with the requirements of 35 U.S.C. § 112 and 35U.S.C. § 132(a).

The grammatical articles “one”, “a”, “an”, and “the”, as used in thisspecification, are intended to include “at least one” or “one or more”,unless otherwise indicated. Thus, the articles are used in thisspecification to refer to one or more than one (i.e., to “at least one”)of the grammatical objects of the article. By way of example, “acomponent” means one or more components, and thus, possibly, more thanone component is contemplated and may be employed or used in animplementation of the described implementations. Further, the use of asingular noun includes the plural, and the use of a plural noun includesthe singular, unless the context of the usage requires otherwise.

As used herein, the term “functionality” refers to the average number ofreactive hydroxyl groups, —OH, present per molecule of the —OHfunctional material that is being described. In the production ofpolyurethane foams, the hydroxyl groups react with isocyanate groups,—NCO, that are attached to the isocyanate compound. The term “hydroxylnumber” refers to the number of reactive hydroxyl groups available forreaction, and is expressed as the number of milligrams of potassiumhydroxide equivalent to the hydroxyl content of one gram of the polyol(ASTM D4274-16). The term “equivalent weight” refers to the weight of acompound divided by its valence. For a polyol, the equivalent weight isthe weight of the polyol that will combine with an isocyanate group, andmay be calculated by dividing the molecular weight of the polyol by itsfunctionality. The equivalent weight of a polyol may also be calculatedby dividing 56,100 by the hydroxyl number of the polyol−EquivalentWeight (g/eq)=(56.1×1000)/OH number.

The polyol blends of this specification have a content of —C₂H₄O— unitswithin a specified range. As used in this context, “a content of —C₂H₄O—units” refers to the calculated weight of —C₂H₄O— units present in apolyol that are formed during production of the polyol itself (asopposed to —C₂H₄O— units that may already be present in a reactant usedto prepare the polyol). In the case of a polyether polyol that is analkoxylation reaction product of an H-functional starter and an alkyleneoxide, for example, —C₂H₄O— units can result from use of ethylene oxideas an alkylene oxide and/or use of an H-functional starter containing a—C₂H₄Z— group in which Z represents a Zerewitinoff-active hydrogen atom(sometimes also referred to merely as “active hydrogen”), such as can bethe case where Z represents a hydrogen bonded to N, O or S. In the caseof a polyester polyol that is a reaction product of a carboxylic acidand/or anhydride thereof with a hydroxyl-containing material, —C₂H₄Z—units may result, for example, from use of diethylene glycol as ahydroxyl-containing material. Thus, when it is stated herein that apolyol blend has a content of —C₂H₄O— units of 3 to 6% by weight, basedon total weight of the polyurethane foam-forming composition, it meansthat 3 to 6% by weight of the polyurethane foam-forming composition,based on the total weight of the polyurethane foam-forming composition,is —C₂H₄O— units formed during production of the polyol(s) that areused, as calculated based on the weight of materials used to make thepolyols.

As indicated, certain implementations of the present specificationrelate to isocyanate-reactive compositions useful in the production ofrigid foams. A rigid foam is characterized as having a ratio ofcompressive strength to tensile strength of at least 0.5:1, elongationof less than 10%, as well as a low recovery rate from distortion and alow elastic limit, as described in in “Polyurethanes: Chemistry andTechnology, Part II Technology,” J. H. Saunders & K. C. Frisch,Interscience Publishers, 1964, page 239.

The rigid foams of this specification are the reaction product of apolyurethane-foam forming composition that includes a polyisocyanate. Asused herein, the term “polyisocyanate” encompasses diisocyanates, aswell as isocyanates of greater functionality than 2.0.

Any of the known organic isocyanates, modified isocyanates orisocyanate-terminated prepolymers made from any of the known organicisocyanates may be used. Suitable organic isocyanates include aromatic,aliphatic, and cycloaliphatic polyisocyanates and combinations thereof.Useful isocyanates include: diisocyanates such as m-phenylenediisocyanate, p-phenylene diisocyanate, 2,4-toluene diisocyanate,2,6-toluene diisocyanate, 1,6-hexamethylene diisocyanate,1,4-hexamethylene diisocyanate, 1,3-cyclohexane diisocyanate,1,4-cyclo-hexane diisocyanate, isomers of hexahydro-toluenediisocyanate, isophorone diisocyanate, dicyclo-hexylmethanediisocyanates, 1,5-naphthylene diisocyanate, 4,4′-diphenylmethanediisocyanate, 2,4′-diphenylmethane diisocyanate, 4,4′-biphenylenediisocyanate, 3,3′-dimethoxy-4,4′-biphenylene diisocyanate and3,3′-dimethyl-diphenyl-propane-4,4′-diisocyanate; triisocyanates such as2,4,6-toluene triisocyanate; and polyisocyanates such as4,4′-dimethyl-diphenylmethane-2,2′,5,5′-tetraisocyanate and thepolymethylene polyphenyl-polyisocyanates.

Undistilled or crude polyisocyanates may also be used. The crude toluenediisocyanate obtained by phosgenating a mixture of toluene diamines andthe crude diphenylmethane diisocyanate obtained by phosgenating crudediphenylmethanediamine (polymeric MDI) are examples of suitable crudepolyisocyanates. Suitable undistilled or crude polyisocyanates aredisclosed in U.S. Pat. No. 3,215,652.

Modified isocyanates are obtained by chemical reaction of diisocyanatesand/or polyisocyanates. Useful modified isocyanates include, but are notlimited to, those containing ester groups, urea groups, biuret groups,allophanate groups, carbodiimide groups, isocyanurate groups, uretdionegroups and/or urethane groups. Examples of modified isocyanates includeprepolymers containing NCO groups and having an NCO content of from 25to 35 weight percent, such as from 29 to 34 weight percent, such asthose based on polyether polyols or polyester polyols anddiphenylmethane diisocyanate.

In certain implementations, the polyisocyanate comprises amethylene-bridged polyphenyl polyisocyanate and/or a prepolymer ofmethylene-bridged polyphenyl polyisocyanates having an averagefunctionality of from 1.8 to 3.5, such as from 2.0 to 3.1, isocyanatemoieties per molecule and an NCO content of from 25 to 32 weightpercent, due to their ability to cross-link the polyurethane.

The isocyanate-reactive compositions described in this specificationcomprise a polyol blend. More specifically, the polyol blend comprisesan aromatic amine-initiated polyether polyol. As used herein, “aromaticamine-initiated polyether polyol” refers to a polyether polyol that isthe reaction product of an H-functional starter comprising an aromaticamine, such as toluenediamine (“TDA”), with alkylene oxide.

In certain implementations, aromatic amine employed has an aminefunctionality of at least 1, such as 1 to 3 or 1 to 2. Specific examplesof suitable aromatic amines which can be used include crude TDA obtainedby the nitration of toluene followed by reduction; 2,3-TDA, 3,4-TDA,2,4-TDA, 2,6-TDA or mixtures thereof; aniline; 4,4′-methylene dianiline;methylene-bridged polyphenyl polyamines composed of isomers of methylenedianilines and triamines or polyamines of higher molecular weightprepared by reacting aniline with formaldehyde by methods known in theart. In some implementations, a mixture composed of 2,3-TDA and 3,4-TDA(commonly referred to as “o-TDA”) is used.

In addition to the aromatic amine, other H-functional starters may alsobe used to prepare the aromatic amine-initiated polyether polyol. Theseother H-functional starters include, for example, water, propyleneglycol, glycerin, ethylene glycol, ethanol amines, diethylene glycol, ora mixture of any two or more thereof. As will be appreciated, it ispossible to use a wide variety of individual starters in combinationwith one another. In some implementations, however, aromatic amine isthe predominant or essentially sole H-functional starter used to producethe aromatic amine-initiated polyether polyol. This means that, in theseimplementations, aromatic amine is present in an amount of more than 50%by weight, such as at least 80% by weight, at least 90% by weight, oreven 100% by weight, based on the total weight of H-functional starterused to produce the aromatic amine-initiated polyether polyol.

A variety of alkylene oxides may be used to produce the aromaticamine-initiated polyether polyol, such as ethylene oxide, propyleneoxide, butylene oxide, amylene oxide and mixtures thereof. The alkyleneoxides may be added individually, sequentially one after the other toform blocks or in a mixture to form a heteric polyether. The aromaticamine-initiated polyether polyols may have primary or secondary hydroxylend groups. In some implementations, propylene oxide is the primary oressentially sole alkylene oxide used to prepare the aromaticamine-initiated polyether polyol. This means that, in theseimplementations, propylene oxide is used in an amount of more than 50%by weight, such as at least 80% by weight, at least 90% by weight, oreven 100% by weight, based on the total weight of alkylene oxide used toprepare the aromatic amine-initiated polyether polyol. In someimplementations, ethylene oxide is employed in a relatively smallamount. In these implementations, ethylene oxide is used in an amount ofno more than 10% by weight, no more than 5% by weight, no more than 1%by weight, or, in some cases, 0% by weight, based on the total weight ofalkylene oxide used to prepare the aromatic amine-initiated polyetherpolyol.

As indicated earlier, the aromatic amine-initiated polyether polyol hasan OH number of 200 to 600 mg KOH/g and a functionality of at least 2.5.In some implementations, the aromatic amine-initiated polyether polyolhas an OH number of 300 to 500 mg KOH/g, such as 380 to 420 mg KOH/g andan average functionality of 3.5 to 4.5, 3.8 to 4.2 or 4.0. In addition,the aromatic amine-initiated polyether polyol, in some implementations,has a content of —C₂H₄O— units of less than 10% by weight, such as lessthan 5% by weight, less than 2% by weight, or, in some cases, 0% byweight, based on total weight of the aromatic amine-initiated polyetherpolyol.

The foregoing aromatic amine-initiated polyether polyol is present in anamount of at least 30% by weight, based on the total weight of polyol.More specifically, in some implementations, the foregoing aromaticamine-initiated polyol is present in an amount of 30 to 80% by weight,such as 30 to 60% by weight, or, in some cases, 40 to 60% by weight or40 to 50% by weight, based on the total weight of the polyol blend.

The polyol blend also includes a saccharide-initiated polyether polyol.As used herein, “saccharide-initiated polyether polyol” refers to apolyether polyol that is the reaction product of an H-functional startercomprising saccharide, such as sucrose, with alkylene oxide. Examples ofsuitable alkylene oxides include ethylene oxide, propylene oxide,butylene oxide, styrene oxide, epichlorohydrin, or a mixture of any twoor more thereof. Some examples of suitable saccharide initiators aresucrose, sorbitol, maltitol, etc. as well as other mono-saccharides,di-saccharides, tri-saccharides and polysaccharides. Other initiatorcompounds are often used in combination with the saccharide initiator toprepare the saccharide initiated polyether polyol. Saccharides can beco-initiated with for example, compounds such as water, propyleneglycol, glycerin, ethylene glycol, ethanol amines, diethylene glycol, ora mixture of any two or more thereof. As will be appreciated, it ispossible to use a wide variety of individual initiator compounds incombination with saccharide initiator.

In some implementations, saccharide is the predominant H-functionalstarter used to produce the saccharide-initiated polyether polyol. Thismeans that, in these implementations, saccharide is present in an amountof more than 50% by weight, such as at least 70% by weight or at least80% by weight, based on the total weight of H-functional starter used toproduce the saccharide-initiated polyether polyol.

In some implementations, propylene oxide is the primary or essentiallysole alkylene oxide used to prepare the saccharide-initiated polyetherpolyol. This means that, in these implementations, propylene oxide isused in an amount of more than 50% by weight, such as at least 60% byweight, or at least 70% by weight, based on the total weight of alkyleneoxide used to prepare the saccharide-initiated polyether polyol. In someimplementations, ethylene oxide is employed in a relatively smallamount. Thus, in these implementations, ethylene oxide is present in anamount of no more than 50% by weight, such as no more than 40% byweight, or, in some cases, no more than 30% by weight, based on thetotal weight of alkylene oxide used to prepare that saccharide-initiatedpolyether polyol.

In some implementations, the saccharide-initiated polyether polyol hasan OH number of from 200 to 600 mg KOH/g, such as 300 to 550 mg KOH/g,such as 380 to 500 mg KOH/g, or, in some cases, 450 to 500 mg KOH/g, anda functionality of 4 to 6, such as 5 to 6, 5.2 to 5.8, or 5.2 to 5.6. Inaddition, in some implementations, the saccharide-initiated polyetherpolyol has a content of —C₂H₄O— units of less than 50% by weight, suchas less than 40% by weight, or no more than 30% by weight, based ontotal weight of the saccharaide-initiated polyether polyol.

The saccharide-initiated polyether polyol is present in an amount of atleast 30% by weight, based on the total weight of polyol. Morespecifically, in some implementations, the saccharide-initiated polyolis present in an amount of 30 to 60% by weight, such as 30 to 50% byweight, or, in some cases, 35 to 45% by weight, based on the totalweight of the polyol blend.

In some implementations, the polyol blend comprises an aromaticpolyester polyol. Suitable aromatic polyester polyols include, forexample, the reaction product of an aromatic diacid or anhydride with asuitable glycol or triol. For example, polyester polyols can be thereaction product of a glycol and/or triol, such as ethylene glycol,propylene glycol, butylene glycol, 1,3-butanediol, neopentyl glycol,diethylene glycol, dipropylene glycol, triethylene glycol, tripropyleneglycol, glycerol, trimethylolethane, trimethyolpropane, pentanediol,hexanediol, heptanediol, 1,3- and 1,4-dimethylol cyclohexane, or amixture of any two or more thereof with an aromatic diacid or aromaticanhydride, such as, for example, phthalic acid, isophthalic acid,terephthalic acid, phthalic anhydride, or a mixture of any two or morethereof. Some of examples of the suitable aromatic polyester polyolsinclude those compounds which are available from Stepan Chemical underthe Stepanpol trade name such as, for example, Stepanpol® PS 3024 andStepanpol PS 2502A or from Invista under the Terate trade name, such asTerate® HT-5100 and HT-5500, or from Coim under the Isoexter trade namesuch as Isoexter® TB-265.

In certain implementations, the aromatic polyester polyol has an OHnumber of 150 to 410 mg KOH/g, such as 150 to 360 mg KOH/g, such as 200to 335 mg KOH/g, or, in some cases, 200 to 250 mg KOH/g, and afunctionality of 1.5 to 3, such as 1.9 to 2.5. In some implementations,the aromatic polyester polyol has a content of —C₂H₄O— units of lessthan 50% by weight, based on total weight of the aromatic polyesterpolyol.

The aromatic polyester polyol is utilized in an amount of 1 to 25%,based on total weight of the polyol blend. In some implementations, thearomatic polyester polyol is present in an amount of 5 to 25% by weight,5 to 20% by weight, or 10 to 20% by weight, based upon the total weightof the polyol blend.

In certain implementations, the aromatic amine-initiated polyetherpolyol and the saccharide-initiated polyether polyol are present in aweight ratio of at least 0.8:1, such as 1:1 to 5:1, 1:1 to 2:1 or, insome cases, 1:1 to 1.5:1. In certain implementations, the aromaticamine-initiated polyether polyol and the aromatic polyester polyol arepresent in a weight ratio of at least 1:1, such as 1:1 to 5:1, 2:1 to4:1 or 2.5:1 to 3.5:1. In certain implementations, thesaccharide-initiated polyether polyol and the aromatic polyester polyolare present in a weight ratio of at least 1:1, such as 1:1 to 5:1, 2:1to 4:1 or, in some cases, 2.5:1 to 3.0:1.

If desired, the polyol blend may include additional compounds thatcontain isocyanate-reactive groups, such as chain extenders and/orcrosslinking agents, and higher molecular weight polyether polyols andpolyester polyols not described above. Chain extenders and/orcrosslinking agents include, for example, ethylene glycol, propyleneglycol, butylene glycol, glycerol, diethylene glycol, dipropyleneglycol, dibutylene glycol, trimethylolpropane, pentaerythritol, ethylenediamine, and diethyltoluenediamine.

In certain implementations, the polyol blend has a weighted averagefunctionality of from 3 to 5, such as 3.5 to 4.5 or 3.8 to 4.2, and/or aweighted average hydroxyl number of from 300 to 500 mg KOH/g, such as350 to 450 mg KOH/g. In certain embodiments, the polyol blend is presentin the polyurethane foam-forming composition in an amount of at least50% by weight, such as 50 to 90% by weight or 60 to 80% by weight, basedon the total weight of the polyurethane foam-forming composition exceptfor the weight of the polyisocyanate.

As earlier indicated, one aspect of the inventions of this specificationis that the polyol blend has a content of —C₂H₄O— units of 3 to 6% byweight, based on total weight of the polyurethane foam-formingcomposition. In some implementation, the polyol blend has a content of—C₂H₄O— units of 4 to 6% by weight, based on total weight of thepolyurethane foam-forming composition.

In some implementations, the sum of the amount of the aromaticamine-initiated polyether polyol, the saccharide-initiated polyetherpolyol, and the aromatic polyester polyol is at least 90% by weight,such as at least 95% by weight, at least 98% by weight, or, in somecases, 100% by weight, based on the total weight of the polyol blend.

Further, in some implementations, the polyol blend does not include anyfilled polyol. As will be appreciated, a “filled polyol” is a dispersionof polymer particles in a base polyol. Examples of filled polyols, anyor all of which are excluded from use in the some implementations of thepolyol blends employed in the inventions disclosed herein, are “polymerpolyols”, in which the polymer particles comprise a polymer comprisingthe free radical polymerization reaction product of an ethylenicallyunsaturated compound, “PIPA polyols”, in which the polymer particlescomprise a polyisocyanate polyaddition polymer comprising the reactionproduct of a polymerizable composition comprising an isocyanate and analkanolamine, and “PHD polyols” in which the polymer particles comprisea polyhydrazodiconamide comprising the reaction product of a reactionmixture comprising an isocyanate and a diamine and/or a hydrazine.

As indicated, the polyurethane foam-forming compositions of thisspecification further comprises a physical blowing agent compositioncomprising a HCFO. Suitable HCFOs include1-chloro-3,3,3-trifluoropropene (HCFO-1233zd, E and/or Z isomers),2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), HCFO1223,1,2-dichloro-1,2-difluoroethene (E and/or Z isomers),3,3-dichloro-3-fluoropropene, 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 (Eand/or Z isomers), 2-chloro-1,1,1,3,4,4,4-heptafluorobutene-2 (E and/orZ isomers). In some implementations, the boiling point, at atmosphericpressure, of the HCFO is at least −25° C., at least −20° C., or, in somecases, at least −19° C., and 40° C. or less, such as 35° C. or less, or,in some cases 33° C. or less. The HCFO may have a boiling point, atatmospheric pressure, of, for example, −25° C. to 40° C., or −20° C. to35° C., or −19° C. to 33° C.

In some implementations, the HCFO is utilized in an amount of at least10% by weight, such as 10 to 30% by weight or 15 to 25% by weight or 18to 22% by weight, based on the total weight of the polyurethanefoam-forming composition except for the weight of the polyisocyanate.

If desired, the isocyanate-reactive composition may include one or moreother physical blowing agents, such as other halogenated blowing agents,such as CFCs, HCFCs, HFCs, other HFOs (aside from HCFO) and/orhydrocarbon blowing agents, such as butane, n-pentane, cyclopentane,hexane, and/or isopentane (i.e. 2-methylbutane). In other embodiments,however, the isocyanate-reactive composition is substantially or, insome cases, completely free, of such other physical blowing agents.Therefore, in some implementations, the HCFO is present in amount of atleast 80% by weight, such as at least 90% by weight, at least 95% byweight, at least 99% by weight or, in some cases 100% by weight, basedon the total weight of the physical blowing agent in the blowing agentcomposition.

The polyurethane foam-forming compositions of this specification includea carbon dioxide generating chemical blowing agent, such as water and/ora formate-blocked amine, is also included. In some of theseimplementations, the carbon dioxide generating chemical blowing agent,such as water, is utilized in an amount of from 0.5 to 5.0% by weight,such as 1 to 3% by weight, or 1.0 to 2.0% by weight, or 1.2 to 1.8% byweight, based on the total weight of the polyurethane foam-formingcomposition except for the weight of the polyisocyanate.

In certain implementations, the physical blowing agent composition andthe carbon dioxide generating chemical blowing agent are present in arelative ratio, by weight, of at least 5:1, such as 5:1 to 50:1, 5:1 to20:1 or, in some cases, 10:1 to 15:1.

The polyurethane foam-forming composition also typically comprises asurfactant. Suitable surfactant include, for example, organosiliconcompounds, such as polysiloxane-polyalkyene-block copolymers, such as apolyether-modified polysiloxane. Other possible surfactants includepolyethylene glycol ethers of long chain alcohols, tertiary amine oralkanolamine salts of long chain alkyl acid sulfate esters,alkylsulfonic esters, or alkylarylsulfonic acids. Such surfactants areemployed in amounts sufficient to stabilize the foaming reaction mixtureagainst collapse and the formation of large and uneven cells. In someimplementations, surfactant is utilized in an amount of 0.2 to 5.0% byweight, such as 1 to 3% by weight, based on the total weight of thepolyurethane foam-forming composition except for the weight of thepolyisocyanate.

The polyurethane foam-forming compositions of this specification alsotypically comprise a catalyst, such as a tertiary amine, tertiaryphosphine, a metal chelate, an acid metal salt, a strong base, a metalalcoholate and/or phenolate, a metal salt of an organic acid, or acombination thereof. In some implementations, the catalyst comprises anorganotin catalyst and/or tertiary amine catalyst. For example, in somecases, a combination of at least one “blowing” catalyst, which stronglypromotes the reaction of an isocyanate group with a water molecule toform carbon dioxide, and either at least one “gelling” catalyst, whichstrongly promotes the reaction of an alcohol group with an isocyanate toform the urethane, or at least one trimerization catalyst, may be used.

Specific examples of suitable tertiary amine catalysts include:pentamethyldiethylenetriamine, N,N-dimethylcyclohexylamine,N,N′,N″-tris(3-dimethylaminopropyl-)hexahydrotriazine,tetramethylethylenediamine, tetraethylene diamine, benzyldimethylamineor a combination thereof. In certain embodiments, the tertiary aminecatalyst includes pentamethyldiethylenetriamine,N,N′,N″-dimethylaminopropyl-hexahydrotriazine,N,N-dimethylcyclohexylamine, or a combination thereof. Specific examplesof suitable organometallic catalysts include dibutyltin dilaurate,dibutyltin diacetate, stannous octoate, potassium octoate, potassiumacetate, potassium 2-ethylhexanoate, or a combination thereof. In someimplementations, catalyst is present in an amount of 0.01 to 3.0% byweight or 0.3 to 2.5% by weight, based on the total weight of thepolyurethane foam-forming composition except for the weight of thepolyisocyanate.

Additional materials which may optionally be included in thefoam-forming compositions of the present invention include: pigments,colorants, fillers, antioxidants, flame retardants, and stabilizers.Exemplary flame retardants useful in the foam-forming composition of thepresent invention include, but are not limited to, reactive brominebased compounds known to be used in polyurethane chemistry andchlorinated phosphate esters, including but not limited to,tri(2-chloroethyl)phosphate (TECP), tri(1,3-dichloro-2-propyl)phosphate,tri(1-chloro-2-propyl)phosphate (TCPP) and dimethyl propyl phosphate(DMPP).

This specification is also directed to processes for producing rigidpolyurethane foams. In such processes, a polyisocyanate is reacted withan isocyanate-reactive composition comprising the polyol blend. In someimplementations, the isocyanate functional component and the polyolblend are mixed at an isocyanate index of from 0.90 to 1.50, such as1.20 to 1.50.

The polyol blend is reacted with an polyisocyanate in the presence ofthe blowing agent composition, the catalyst composition, a surfactantand any other optional ingredients. The rigid foams may be prepared byblending all of the polyurethane foam-forming composition components,except for the polyisocyanate, together in a phase stable mixture, andthen mixing this mixture in the proper ratio with the polyisocyanate.Alternatively, one or more of the components, such as the surfactant,may be combined with the polyisocyanate prior to mixing it with thepolyol blend. Other possible implementations would include adding one ormore of the components as a separate stream, together with the polyolblend and polyisocyanate. As used herein, the term phase stable meansthat the composition does not visibly separate when stored for 7 days atabout 70° F. (or 21° C.).

Many foam machines are designed to condition and mix only two componentsin the proper ratio. For use of these machines, a premix of all thecomponents except the polyisocyanate can be advantageously employed.According to the two-component method (component A: polyisocyanate; andcomponent B: isocyanate-reactive composition which typically includesthe polyol blend, blowing agent, water, catalyst and surfactant), thecomponents may be mixed in the proper ratio at a temperature of 5 to 50°C., such as 15 to 35° C., injected or poured into a mold having thetemperature controlled to within a range of from 20 to 70° C., such as35 to 60° C. The mixture then expands to fill the cavity with the rigidpolyurethane foam. This simplifies the metering and mixing of thereacting components which form the foam-forming mixture, but requiresthat the isocyanate reactive composition be phase stable.

Alternatively, the rigid polyurethane foams may also be prepared by theso-called “quasi prepolymer” method. In this method, a portion of thepolyol component is reacted in the absence of the urethane-formingcatalysts with the polyisocyanate component in proportion so as toprovide from 10 percent to 35 percent of free isocyanate groups in thereaction product based on the prepolymer. To prepare foam, the remainingportion of the polyol is added and the components are allowed to reacttogether in the presence of the blowing agent and other appropriateadditives such as the catalysts, and surfactants. Other additives may beadded to either the isocyanate prepolymer or remaining polyol or bothprior to the mixing of the components, whereby at the end of thereaction, rigid foam is provided.

Furthermore, the rigid foam can be prepared in a batch or continuousprocess by the one-shot or quasi-prepolymer methods using any well-knownfoaming apparatus. The rigid foam may be produced in the form of slabstock, moldings, cavity fillings, sprayed foam, frothed foam orlaminates with other materials such as hardboard, plasterboard,plastics, paper or metal as facer substrates.

For closed-cell insulating foams, the object is to retain the blowingagent in the cells to maintain a low thermal conductivity of theinsulating material, i.e., the rigid foam. Thus, high closed-cellcontent in the foam is desirable. In some implementations, the rigidfoams produced according to implementations of this specification have aclosed-cell content of more than 80 percent, more than 85 percent, ormore than 88 percent, as measured according to ASTM D6226-15.Furthermore, the thermal conductivity of foams produced according tovarious implementations of the present specification indicates that thefoams have acceptable insulating properties, i.e., the foams have athermal conductivity measured at 35° F. (2° C.) of less than 0.126BTU-in/h-ft²-° F. and measured at 75° F. (24° C.) of less than 0.140BTU-in/h-ft²-° F. for foam from the core of 2-inch thick panels, asmeasured according to ASTM C518-15.

This specification also relates to the use of the rigid foams describedherein for thermal insulation. That is, the rigid foams of the presentspecification may find use as an insulating material in refrigerationapparatuses. These rigid foams can be used, for example, as anintermediate layer in composite elements or for filling hollow spaces ofrefrigerators and freezers, or refrigerated trailers. These foams mayalso find use in the construction industry or for thermal insulation oflong-distance heating pipes and containers.

As such, the present invention also provides a composite articlecomprising rigid foam as disclosed herein sandwiched between one or morefacer substrates. In certain implementations, the facer substrate may beplastic (such a polypropylene resin reinforced with continuousbi-directional glass fibers or a fiberglass reinforced polyestercopolymer), paper, wood, or metal. For example, in certainimplementations, the composite article may be a refrigeration apparatussuch as a refrigerator, freezer, or cooler with an exterior metal shelland interior plastic liner. In certain implementations, therefrigeration apparatus may be a trailer, and the composite article mayinclude the foams produced according to the present invention insandwich composites for trailer floors or sidewalls.

It has been found, surprisingly, that the particular polyurethanefoam-forming compositions described herein are capable, when formulatedwith appropriate additives (surfactants, catalysts, etc.), of producingrigid polyurethane foams with similar, or even significantly improved,thermal insulation properties (as determined by K-factor measurements)while utilizing a reduced amount of costly HCFO physical blowing agent,while still retaining other important foam properties and processingcharacteristics, such as dimensional stability, compressive strength,flow, reactivity and de-mold characteristics.

Various aspects of the subject matter described herein are set out inthe following numbered clauses:

Clause 1. A polyurethane foam-forming composition comprising: (a) apolyol blend comprising: (1) at least 30% by weight, based on totalweight of the polyol blend, of an aromatic amine-initiated polyetherpolyol having a functionality of at least 2.5 and an OH number of 200 to600 mg KOH/g; (2) at least 30% by weight, based on total weight of thepolyol blend, of a saccharide-initiated polyether polyol having afunctionality of 4 to 6 and an OH number of 200 to 600 g/KOH gram; and(3) 1 to 25% by weight, based on total weight of the polyol blend, of anaromatic polyester polyol having a functionality of 1.5 to 3 and an OHnumber of 150 to 410 mg KOH/g, wherein the sum of the amount of thearomatic amine-initiated polyether polyol, the saccharide-initiatedpolyether polyol, and the aromatic polyester polyol is at least 90% byweight, based on the total weight of the polyol blend, and the polyolblend has a content of —C₂H₄O— units of 3 to 6% by weight, based on thetotal weight of the polyurethane foam-forming composition; (b) a blowingagent composition comprising: (1) a physical blowing agent and (2) acarbon dioxide-generating chemical blowing agent, wherein (i) thephysical blowing agent comprises a hydrochlorofluoroolefin that ispresent in an amount of 5% to 15% by weight, based on total weight ofthe polyurethane foam-forming composition and in an amount of at least80% by weight, based on total weight of physical blowing agent in theblowing agent composition, and (ii) the physical blowing agentcomposition and the carbon dioxide generating chemical blowing agent arepresent in a relative ratio, by weight, of 5:1 to 50:1; and (c) apolyisocyanate present in an amount sufficient to provide an isocyanateindex of 1.15 to less than 1.40.

Clause 2. The polyurethane foam-forming composition of clause 1, whereinthe aromatic amine used to produce the aromatic amine-initiatedpolyether polyol has an amine functionality of at least 1, 1 to 3, or 1to 2.

Clause 3. The polyurethane foam-forming composition of clause 1 orclause 2, wherein the aromatic amine used to produce the aromaticamine-initiated polyether polyol comprises 2,3-TDA, 3,4-TDA, 2,4-TDA,2,6-TDA or a mixture thereof, such as a mixture comprising 2,3-TDA and3,4-TDA.

Clause 4. The polyurethane foam-forming composition of any one of clause1 to clause 3, wherein aromatic amine is present in an amount of morethan 50% by weight, at least 80% by weight, at least 90% by weight, or100% by weight, based on the total weight of H-functional starter usedto produce the aromatic amine-initiated polyether polyol.

Clause 5. The polyurethane foam-forming composition of any one of clause1 to clause 4, wherein propylene oxide is used in an amount of more than50% by weight, at least 80% by weight, at least 90% by weight, or 100%by weight, based on total weight of alkylene oxide used to prepare thearomatic amine-initiated polyether polyol.

Clause 6. The polyurethane foam-forming composition of clause 5, whereinethylene oxide is used in an amount of no more than 10% by weight, nomore than 5% by weight, no more than 1% by weight, or 0% by weight,based on the total weight of alkylene oxide used to prepare the aromaticamine-initiated polyether polyol.

Clause 7. The polyurethane foam-forming composition of any one of clause1 to clause 6, wherein the aromatic amine-initiated polyether polyol hasan OH number of 300 to 500 mg KOH/g or 380 to 420 mg KOH/g and/or anaverage functionality of 3.5 to 4.5, 3.8 to 4.2 or 4.0.

Clause 8. The polyurethane foam-forming composition of any one of clause1 to clause 7, wherein the aromatic amine-initiated polyether polyol hasa content of —C₂H₄O— units of less than 10% by weight, less than 5% byweight, less than 2% by weight, or 0% by weight, based on total weightof the aromatic amine-initiated polyether polyol.

Clause 9. The polyurethane foam-forming composition of any one of clause1 to clause 8, wherein the aromatic amine-initiated polyether polyol ispresent in an amount of 30 to 80% by weight, 30 to 60% by weight, 40 to60% by weight or 40 to 50% by weight, based on the total weight of thepolyol blend.

Clause 10. The polyurethane foam-forming composition of any one ofclause 1 to clause 9, wherein saccharide is present in an amount of morethan 50% by weight, at least 70% by weight or at least 80% by weight,based on the total weight of H-functional starter used to produce thesaccharide-initiated polyether polyol.

Clause 11. The polyurethane foam-forming composition of any one ofclause 1 to clause 10, wherein propylene oxide is present in an amountof more than 50% by weight, at least 60% by weight, or at least 70% byweight, based on the total weight of alkylene oxide used to prepare thesaccharide-initiated polyether polyol.

Clause 12. The polyurethane foam-forming composition of clause 11,wherein ethylene oxide is present in an amount of no more than 50% byweight, no more than 40% by weight, or no more than 30% by weight, basedon the total weight of alkylene oxide used to prepare thatsaccharide-initiated polyether polyol.

Clause 13. The polyurethane foam-forming composition of any one ofclause 1 to clause 12, wherein the saccharide-initiated polyether polyolhas an OH number of 200 to 600 mg KOH/g, 300 to 550 mg KOH/g, 380 to 500mg KOH/g, or 450 to 500 mg KOH/g, and/or a functionality of 4 to 6, 5 to6, 5.2 to 5.8, or 5.2 to 5.6.

Clause 14. The polyurethane foam-forming composition of any one ofclause 1 to clause 13, wherein the saccharide-initiated polyether polyolhas a content of —C₂H₄O— units of less than 50% by weight, less than 40%by weight, or no more than 30% by weight, based on total weight of thesaccharide-initiated polyether polyol.

Clause 15. The polyurethane foam-forming composition of any one ofclause 1 to clause 14, wherein the saccharide-initiated polyol ispresent in an amount of 30 to 60% by weight, 30 to 50% by weight, or 35to 45% by weight, based on the total weight of the polyol blend.

Clause 16. The polyurethane foam-forming composition of any one ofclause 1 to clause 15, wherein the aromatic polyester polyol has an OHnumber of 150 to 360 mg KOH/g, 200 to 335 mg KOH/g, or 200 to 250 mgKOH/g, and/or a functionality of 1.5 to 3 or 1.9 to 2.5.

Clause 17. The polyurethane foam-forming composition of any one ofclause 1 to clause 16, wherein the aromatic polyester polyol has acontent of —C₂H₄O— units of less than 50% by weight, based on totalweight of the aromatic polyester polyol.

Clause 18. The polyurethane foam-forming composition of any one ofclause 1 to clause 17, wherein the aromatic polyester polyol is presentin an amount of 5 to 25% by weight, 5 to 20% by weight, or 10 to 20% byweight, based upon the total weight of the polyol blend.

Clause 19. The polyurethane foam-forming composition of any one ofclause 1 to clause 18, wherein the aromatic amine-initiated polyetherpolyol and the saccharide-initiated polyether polyol are present in aweight ratio of at least 0.8:1, 1:1 to 5:1, 1:1 to 2:1 or 1:1 to 1.5:1.

Clause 20. The polyurethane foam-forming composition of any one ofclause 1 to clause 19, wherein the aromatic amine-initiated polyetherpolyol and the aromatic polyester polyol are present in a weight ratioof at least 1:1, 1:1 to 5:1, 2:1 to 4:1 or 2.5:1 to 3.5:1.

Clause 21. The polyurethane foam-forming composition of any one ofclause 1 to clause 20, wherein the saccharide-initiated polyether polyoland the aromatic polyester polyol are present in a weight ratio of atleast 1:1, 1:1 to 5:1, 2:1 to 4:1 or, 2.5:1 to 3.0:1.

Clause 22. The polyurethane foam-forming composition of any one ofclause 1 to clause 21, wherein the polyol blend has a weighted averagefunctionality of 3 to 5, such as 3.5 to 4.5 or 3.8 to 4.2, and/or aweighted average hydroxyl number of 300 to 500 mg KOH/g, such as 350 to450 mg KOH/g.

Clause 23. The polyurethane foam-forming composition of any one ofclause 1 to clause 22, wherein the polyol blend is present in thepolyurethane foam-forming composition in an amount of at least 50% byweight, 50 to 90% by weight or 60 to 80% by weight, based on the totalweight of the polyurethane foam-forming composition except for theweight of the polyisocyanate.

Clause 24. The polyurethane foam-forming composition of any one ofclause 1 to clause 23, wherein the polyol blend has a content of —C₂H₄O—units of 4 to 6% by weight, based on total weight of the polyurethanefoam-forming composition.

Clause 25. The polyurethane foam-forming composition of any one ofclause 1 to clause 24, wherein the sum of the amount of the aromaticamine-initiated polyether polyol, the saccharide-initiated polyetherpolyol, and the aromatic polyester polyol is at least 90% by weight, atleast 95% by weight, at least 98% by weight, or 100% by weight, based onthe total weight of the polyol blend.

Clause 26. The polyurethane foam-forming composition of any one ofclause 1 to clause 25, wherein the polyol blend does not include anyfilled polyol, such as polymer polyol, PIPA polyol and/or PHD polyol.

Clause 27. The polyurethane foam-forming composition of any one ofclause 1 to clause 26, wherein the HCFO comprises1-chloro-3,3,3-trifluoropropene (HCFO-1233zd, E and/or Z isomer),2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), HCFO1223,1,2-dichloro-1,2-difluoroethene (E and/or Z isomer),3,3-dichloro-3-fluoropropene, 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 (Eand/or Z isomer), 2-chloro-1,1,1,3,4,4,4-heptafluorobutene-2 (E and/or Zisomer.

Clause 28. The polyurethane foam-forming composition of any one ofclause 1 to clause 27, wherein the boiling point, at atmosphericpressure, of the HCFO is at least −25° C., at least −20° C., or at least−19° C., and 40° C. or less, 35° C. or less, or 33° C. or less, such aswhere the HCFO has a boiling point, at atmospheric pressure, of −25° C.to 40° C., −20° C. to 35° C., or −19° C. to 33° C.

Clause 29. The polyurethane foam-forming composition of any one ofclause 1 to clause 28, wherein HCFO is present in an amount of at least10% by weight, 10 to 30% by weight or 15 to 25% by weight or 18 to 22%by weight, based on the total weight of the polyurethane foam-formingcomposition except for the weight of the polyisocyanate.

Clause 30. The polyurethane foam-forming composition of any one ofclause 1 to clause 29, wherein HCFO is present in amount of at least 90%by weight, at least 95% by weight, at least 99% by weight or 100% byweight, based on the total weight of the physical blowing agent in theblowing agent composition.

Clause 31. The polyurethane foam-forming composition of any one ofclause 1 to clause 30, wherein the carbon dioxide generating chemicalblowing agent comprises water and/or a formate-blocked amine.

Clause 32. The polyurethane foam-forming composition of any one ofclause 1 to clause 31, wherein the carbon dioxide generating chemicalblowing agent is present in an amount of 0.5 to 5.0% by weight, 1 to 3%by weight, 1.0 to 2.0% by weight, or 1.2 to 1.8% by weight, based on thetotal weight of the polyurethane foam-forming composition except for theweight of the polyisocyanate.

Clause 33. The polyurethane foam-forming composition of any one ofclause 1 to clause 32, wherein the physical blowing agent compositionand the carbon dioxide generating chemical blowing agent are present ina relative ratio, by weight, of 5:1 to 20:1 or 10:1 to 15:1.

Clause 34. The polyurethane foam-forming composition of any one ofclause 1 to clause 33, wherein the polyurethane foam-forming compositioncomprises a surfactant, such as a polyether-modified polysiloxane.

Clause 35. The polyurethane foam-forming composition of any one ofclause 1 to clause 34, wherein the polyurethane foam-forming compositioncomprises a catalyst, such as a tertiary amine and/or an organometallic,such as where the tertiary amine comprisespentamethyldiethylenetriamine, N,N-dimethylcyclohexylamine,N,N′,N″-tris(3-dimethylaminopropyl-)hexahydrotriazine,tetramethylethylenediamine, tetraethylene diamine, benzyldimethylamineor a combination thereof and/or the organometallic catalyst comprisesdibutyltin dilaurate, dibutyltin diacetate, stannous octoate, potassiumoctoate, potassium acetate, potassium 2-ethylhexanoate, or a combinationthereof.

Clause 36. A polyurethane foam produced from the polyurethanefoam-forming composition of any one of clause 1 to clause 35, whereinthe polyurethane foam has a closed-cell content of more than 80 percent,more than 85 percent, or more than 88 percent, as measured according toASTM D6226-15.

Clause 37. The polyurethane foam of clause 36, wherein the polyurethanefoam has a thermal conductivity measured at 35° F. (2° C.) of less than0.126 BTU-in/h-ft2-° F. and measured at 75° F. (24° C.) of less than0.140 BTU-in/h-ft2-° F. for foam from the core of 2-inch thick panels,as measured according to ASTM C518-15.

Clause 38. A composite element comprising the polyurethane foam ofclause 36 or clause 37 sandwiched between one or more facer substrates,such as where the facer substrate is constructed of plastic, such apolypropylene resin reinforced with continuous bi-directional glassfibers or a fiberglass reinforced polyester copolymer, paper, wood, ormetal.

Clause 39. A refrigeration apparatus, such as a refrigerator, freezer,trailer, or cooler comprising the composite element of clause 38.

Clause 40. A method of producing a polyurethane foam, comprisingreacting, at an isocyanate index of 1.15 to less than 1.40, apolyurethane foam-forming composition comprising a polyol blend, apolyisocyanate, and a blowing agent composition, wherein: (a) the polyolblend comprises (1) at least 30% by weight, based on total weight of thepolyol blend, of an aromatic amine-initiated polyether polyol having afunctionality of at least 2.5 and an OH number of 200 to 600 mg KOH/g;(2) at least 30% by weight, based on total weight of the polyol blend,of a saccharide-initiated polyether polyol having a functionality of 4to 6 and an OH number of 200 to 600 g/KOH gram; and (3) 1 to 25% byweight, based on total weight of the polyol blend, of an aromaticpolyester polyol having a functionality of 1.5 to 3 and an OH number of150 to 410 mg KOH/g, wherein the polyol blend has a content of —C₂H₄O—units of 3 to 6% by weight, based on the total weight of thepolyurethane foam-forming composition; (b) the blowing agent compositioncomprises: (1) a physical blowing agent and (2) a carbondioxide-generating chemical blowing agent, wherein (i) the physicalblowing agent comprises a hydrochlorofluoroolefin that is present in anamount of 5% to 15% by weight, based on total weight of the polyurethanefoam-forming composition and in an amount of at least 80% by weight,based on total weight of physical blowing agent in the blowing agentcomposition, and (ii) the physical blowing agent composition and thecarbon dioxide generating chemical blowing agent are present in arelative ratio, by weight, of 5:1 to 50:1.

Clause 41. The method of clause 40, wherein the aromatic amine used toproduce the aromatic amine-initiated polyether polyol has an aminefunctionality of at least 1, 1 to 3, or 1 to 2.

Clause 42. The method of clause 40 or clause 41, wherein the aromaticamine used to produce the aromatic amine-initiated polyether polyolcomprises 2,3-TDA, 3,4-TDA, 2,4-TDA, 2,6-TDA or a mixture thereof, suchas a mixture comprising 2,3-TDA and 3,4-TDA.

Clause 43. The method of any one of clause 40 to clause 42, whereinaromatic amine is present in an amount of more than 50% by weight, atleast 80% by weight, at least 90% by weight, or 100% by weight, based onthe total weight of H-functional starter used to produce the aromaticamine-initiated polyether polyol.

Clause 44. The method of any one of clause 40 to clause 43, whereinpropylene oxide is used in an amount of more than 50% by weight, atleast 80% by weight, at least 90% by weight, or 100% by weight, based ontotal weight of alkylene oxide used to prepare the aromaticamine-initiated polyether polyol.

Clause 45. The method of clause 44, wherein ethylene oxide is used in anamount of no more than 10% by weight, no more than 5% by weight, no morethan 1% by weight, or 0% by weight, based on the total weight ofalkylene oxide used to prepare the aromatic amine-initiated polyetherpolyol.

Clause 46. The method of any one of clause 40 to clause 45, wherein thearomatic amine-initiated polyether polyol has an OH number of 300 to 500mg KOH/g or 380 to 420 mg KOH/g and/or an average functionality of 3.5to 4.5, 3.8 to 4.2 or 4.0.

Clause 47. The method of any one of clause 40 to clause 46, wherein thearomatic amine-initiated polyether polyol has a content of —C₂H₄O— unitsof less than 10% by weight, less than 5% by weight, less than 2% byweight, or 0% by weight, based on total weight of the aromaticamine-initiated polyether polyol.

Clause 48. The method of any one of clause 40 to clause 47, wherein thearomatic amine-initiated polyether polyol is present in an amount of 30to 80% by weight, 30 to 60% by weight, 40 to 60% by weight or 40 to 50%by weight, based on the total weight of the polyol blend.

Clause 49. The method of any one of clause 40 to clause 48, whereinsaccharide is present in an amount of more than 50% by weight, at least70% by weight or at least 80% by weight, based on the total weight ofH-functional starter used to produce the saccharide-initiated polyetherpolyol.

Clause 50. The method of any one of clause 40 to clause 49, whereinpropylene oxide is present in an amount of more than 50% by weight, atleast 60% by weight, or at least 70% by weight, based on the totalweight of alkylene oxide used to prepare the saccharide-initiatedpolyether polyol.

Clause 51. The method of clause 50, wherein ethylene oxide is present inan amount of no more than 50% by weight, no more than 40% by weight, orno more than 30% by weight, based on the total weight of alkylene oxideused to prepare that saccharide-initiated polyether polyol.

Clause 52. The method of any one of clause 40 to clause 51, wherein thesaccharide-initiated polyether polyol has an OH number of 200 to 600 mgKOH/g, 300 to 550 mg KOH/g, 380 to 500 mg KOH/g, or 450 to 500 mg KOH/g,and/or a functionality of 4 to 6, 5 to 6, 5.2 to 5.8, or 5.2 to 5.6.

Clause 53. The method of any one of clause 40 to clause 52, wherein thesaccharide-initiated polyether polyol has a content of —C₂H₄O— units ofless than 50% by weight, less than 40% by weight, or no more than 30% byweight, based on total weight of the saccharide-initiated polyetherpolyol.

Clause 54. The method of any one of clause 40 to clause 53, wherein thesaccharide-initiated polyol is present in an amount of 30 to 60% byweight, 30 to 50% by weight, or 35 to 45% by weight, based on the totalweight of the polyol blend.

Clause 55. The method of any one of clause 40 to clause 54, wherein thearomatic polyester polyol has an OH number of 150 to 360 mg KOH/g, 200to 335 mg KOH/g, or 200 to 250 mg KOH/g, and/or a functionality of 1.5to 3 or 1.9 to 2.5.

Clause 56. The method of any one of clause 40 to clause 54, wherein thearomatic polyester polyol has a content of —C₂H₄O— units of less than50% by weight, based on total weight of the aromatic polyester polyol.

Clause 57. The method of any one of clause 40 to clause 55, wherein thearomatic polyester polyol is present in an amount of 5 to 25% by weight,5 to 20% by weight, or 10 to 20% by weight, based upon the total weightof the polyol blend.

Clause 58. The method of any one of clause 40 to clause 56, wherein thearomatic amine-initiated polyether polyol and the saccharide-initiatedpolyether polyol are present in a weight ratio of at least 0.8:1, 1:1 to5:1, 1:1 to 2:1 or 1:1 to 1.5:1.

Clause 59. The method of any one of clause 40 to clause 58, wherein thearomatic amine-initiated polyether polyol and the aromatic polyesterpolyol are present in a weight ratio of at least 1:1, 1:1 to 5:1, 2:1 to4:1 or 2.5:1 to 3.5:1.

Clause 60. The method of any one of clause 40 to clause 59, wherein thesaccharide-initiated polyether polyol and the aromatic polyester polyolare present in a weight ratio of at least 1:1, 1:1 to 5:1, 2:1 to 4:1or, 2.5:1 to 3.0:1.

Clause 61. The method of any one of clause 40 to clause 60, wherein thepolyol blend has a weighted average functionality of 3 to 5, such as 3.5to 4.5 or 3.8 to 4.2, and/or a weighted average hydroxyl number of 300to 500 mg KOH/g, such as 350 to 450 mg KOH/g.

Clause 62. The method of any one of clause 40 to clause 61, wherein thepolyol blend is present in the polyurethane foam-forming composition inan amount of at least 50% by weight, 50 to 90% by weight or 60 to 80% byweight, based on the total weight of the polyurethane foam-formingcomposition except for the weight of the polyisocyanate.

Clause 63. The method of any one of clause 40 to clause 62, wherein thepolyol blend has a content of —C₂H₄O— units of 4 to 6% by weight, basedon total weight of the polyurethane foam-forming composition.

Clause 64. The method of any one of clause 40 to clause 63, wherein thesum of the amount of the aromatic amine-initiated polyether polyol, thesaccharide-initiated polyether polyol, and the aromatic polyester polyolis at least 90% by weight, at least 95% by weight, at least 98% byweight, or 100% by weight, based on the total weight of the polyolblend.

Clause 65. The method of any one of clause 40 to clause 64, wherein thepolyol blend does not include any filled polyol, such as polymer polyol,PIPA polyol and/or PHD polyol.

Clause 66. The method of any one of clause 40 to clause 65, wherein theHCFO comprises 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd, E and/or Zisomer), 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), HCFO1223,1,2-dichloro-1,2-difluoroethene (E and/or Z isomer),3,3-dichloro-3-fluoropropene, 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 (Eand/or Z isomer), 2-chloro-1,1,1,3,4,4,4-heptafluorobutene-2 (E and/or Zisomer.

Clause 67. The method of any one of clause 40 to clause 66, wherein theboiling point, at atmospheric pressure, of the HCFO is at least −25° C.,at least −20° C., or at least −19° C., and 40° C. or less, 35° C. orless, or 33° C. or less, such as where the HCFO has a boiling point, atatmospheric pressure, of −25° C. to 40° C., −20° C. to 35° C., or −19°C. to 33° C.

Clause 68. The method of any one of clause 40 to clause 67, wherein HCFOis present in an amount of at least 10% by weight, 10 to 30% by weight,15 to 25% by weight or 18 to 22% by weight, based on the total weight ofthe polyurethane foam-forming composition except for the weight of thepolyisocyanate.

Clause 69. The method of any one of clause 40 to clause 68, wherein HCFOis present in amount of at least 90% by weight, at least 95% by weight,at least 99% by weight or 100% by weight, based on the total weight ofthe physical blowing agent in the blowing agent composition.

Clause 70. The method of any one of clause 40 to clause 69, wherein thecarbon dioxide generating chemical blowing agent comprises water and/ora formate-blocked amine.

Clause 71. The method of any one of clause 40 to clause 70, wherein thecarbon dioxide generating chemical blowing agent is present in an amountof 0.5 to 5.0% by weight, 1 to 3% by weight, 1.0 to 2.0% by weight, or1.2 to 1.8% by weight, based on the total weight of the polyurethanefoam-forming composition except for the weight of the polyisocyanate.

Clause 72. The method of any one of clause 40 to clause 71, wherein thephysical blowing agent composition and the carbon dioxide generatingchemical blowing agent are present in a relative ratio, by weight, of5:1 to 20:1 or 10:1 to 15:1.

Clause 73. The method of any one of clause 40 to clause 72, wherein thepolyurethane foam-forming composition comprises a surfactant, such as apolyether-modified polysiloxane.

Clause 74. The method of any one of clause 40 to clause 73, wherein thepolyurethane foam-forming composition comprises a catalyst, such as atertiary amine and/or an organometallic, such as where the tertiaryamine comprises pentamethyldiethylenetriamine,N,N-dimethylcyclohexylamine,N,N′,N″-tris(3-dimethylaminopropyl-)hexahydrotriazine,tetramethylethylenediamine, tetraethylene diamine, benzyldimethylamineor a combination thereof and/or the organometallic catalyst comprisesdibutyltin dilaurate, dibutyltin diacetate, stannous octoate, potassiumoctoate, potassium acetate, potassium 2-ethylhexanoate, or a combinationthereof.

Clause 75. A polyurethane foam produced by the method of any one ofclause 40 to clause 74.

Clause 76. The polyurethane foam of clause 75, wherein the polyurethanefoam has a closed-cell content of more than 80 percent, more than 85percent, or more than 88 percent, as measured according to ASTMD6226-15.

Clause 77. The polyurethane foam of clause 76, wherein the polyurethanefoam has a thermal conductivity measured at 35° F. (2° C.) of less than0.126 BTU-in/h-ft2-° F. and measured at 75° F. (24° C.) of less than0.140 BTU-in/h-ft2-° F. for foam from the core of 2-inch thick panels,as measured according to ASTM C518-15.

Clause 78. A composite element comprising the polyurethane foam ofclause 76 or clause 77 sandwiched between one or more facer substrates,such as where the facer substrate is constructed of plastic, such apolypropylene resin reinforced with continuous bi-directional glassfibers or a fiberglass reinforced polyester copolymer, paper, wood, ormetal.

Clause 79. A refrigeration apparatus, such as a refrigerator, freezer,trailer, or cooler comprising the composite element of clause 78.

Clause 80. An isocyanate-reactive composition, comprising: (a) polyolblend comprising: (1) at least 30% by weight, based on total weight ofthe polyol blend, of an aromatic amine-initiated polyether polyol havinga functionality of at least 2.5 and an OH number of 200 to 600 mg KOH/g;(2) at least 30% by weight, based on total weight of the polyol blend,of a saccharide-initiated polyether polyol having a functionality of 4to 6 and an OH number of 200 to 600 g/KOH gram; and (3) 1 to 25% byweight, based on total weight of the polyol blend, of an aromaticpolyester polyol having a functionality of 1.5 to 3 and an OH number of150 to 410 mg KOH/g, wherein the polyol blend has a content of —C₂H₄O—units of 5 to 15% by weight, based on the total weight of theisocyanate-reactive composition; and (b) a blowing agent compositioncomprising: (1) a physical blowing agent and (2) a carbondioxide-generating chemical blowing agent, wherein (i) the physicalblowing agent comprises a hydrochlorofluoroolefin that is present in anamount of 10% to 30% by weight, based on total weight of theisocyanate-reactive composition and in an amount of at least 80% byweight, based on total weight of physical blowing agent in the blowingagent composition, and (ii) the physical blowing agent composition andthe carbon dioxide generating chemical blowing agent are present in arelative ratio, by weight, of 5:1 to 50:1.

Clause 81. The isocyanate-reactive composition of clause 80, wherein thearomatic amine used to produce the aromatic amine-initiated polyetherpolyol has an amine functionality of at least 1, 1 to 3, or 1 to 2.

Clause 82. The isocyanate-reactive composition of clause 80 or clause81, wherein the aromatic amine used to produce the aromaticamine-initiated polyether polyol comprises 2,3-TDA, 3,4-TDA, 2,4-TDA,2,6-TDA or a mixture thereof, such as a mixture comprising 2,3-TDA and3,4-TDA.

Clause 83. The isocyanate-reactive composition of any one of clause 80to clause 82, wherein aromatic amine is present in an amount of morethan 50% by weight, at least 80% by weight, at least 90% by weight, or100% by weight, based on the total weight of H-functional starter usedto produce the aromatic amine-initiated polyether polyol.

Clause 84. The isocyanate-reactive composition of any one of clause 80to clause 83, wherein propylene oxide is used in an amount of more than50% by weight, at least 80% by weight, at least 90% by weight, or 100%by weight, based on total weight of alkylene oxide used to prepare thearomatic amine-initiated polyether polyol.

Clause 85. The isocyanate-reactive composition of clause 84, whereinethylene oxide is used in an amount of no more than 10% by weight, nomore than 5% by weight, no more than 1% by weight, or 0% by weight,based on the total weight of alkylene oxide used to prepare the aromaticamine-initiated polyether polyol.

Clause 86. The isocyanate-reactive composition of any one of clause 80to clause 85, wherein the aromatic amine-initiated polyether polyol hasan OH number of 300 to 500 mg KOH/g or 380 to 420 mg KOH/g and/or anaverage functionality of 3.5 to 4.5, 3.8 to 4.2 or 4.0.

Clause 87. The isocyanate-reactive composition of any one of clause 80to clause 86, wherein the aromatic amine-initiated polyether polyol hasa content of —C₂H₄O— units of less than 10% by weight, less than 5% byweight, less than 2% by weight, or 0% by weight, based on total weightof the aromatic amine-initiated polyether polyol.

Clause 88. The isocyanate-reactive composition of any one of clause 80to clause 87, wherein the aromatic amine-initiated polyether polyol ispresent in an amount of 30 to 80% by weight, 30 to 60% by weight, 40 to60% by weight or 40 to 50% by weight, based on the total weight of thepolyol blend.

Clause 89. The isocyanate-reactive composition of any one of clause 80to clause 88, wherein saccharide is present in an amount of more than50% by weight, at least 70% by weight or at least 80% by weight, basedon the total weight of H-functional starter used to produce thesaccharide-initiated polyether polyol.

Clause 90. The isocyanate-reactive composition of any one of clause 80to clause 89, wherein propylene oxide is present in an amount of morethan 50% by weight, at least 60% by weight, or at least 70% by weight,based on the total weight of alkylene oxide used to prepare thesaccharide-initiated polyether polyol.

Clause 91. The isocyanate-reactive composition of clause 90, whereinethylene oxide is present in an amount of no more than 50% by weight, nomore than 40% by weight, or no more than 30% by weight, based on thetotal weight of alkylene oxide used to prepare that saccharide-initiatedpolyether polyol.

Clause 92. The isocyanate-reactive composition of any one of clause 80to clause 91, wherein the saccharide-initiated polyether polyol has anOH number of 200 to 600 mg KOH/g, 300 to 550 mg KOH/g, 380 to 500 mgKOH/g, or 450 to 500 mg KOH/g, and/or a functionality of 4 to 6, 5 to 6,5.2 to 5.8, or 5.2 to 5.6.

Clause 93. The isocyanate-reactive composition of any one of clause 80to clause 92, wherein the saccharide-initiated polyether polyol has acontent of —C₂H₄O— units of less than 50% by weight, less than 40% byweight, or no more than 30% by weight, based on total weight of thesaccharide-initiated polyether polyol.

Clause 94. The isocyanate-reactive composition of any one of clause 80to clause 93, wherein the saccharide-initiated polyol is present in anamount of 30 to 60% by weight, 30 to 50% by weight, or 35 to 45% byweight, based on the total weight of the polyol blend.

Clause 95. The isocyanate-reactive composition of any one of clause 80to clause 94, wherein the aromatic polyester polyol has an OH number of150 to 360 mg KOH/g, 200 to 335 mg KOH/g, or 200 to 250 mg KOH/g, and/ora functionality of 1.5 to 3 or 1.9 to 2.5.

Clause 96. The isocyanate-reactive composition of any one of clause 80to clause 95, wherein the aromatic polyester polyol has a content of—C₂H₄O— units of less than 50% by weight, based on total weight of thearomatic polyester polyol.

Clause 97. The isocyanate-reactive composition of any one of clause 80to clause 96, wherein the aromatic polyester polyol is present in anamount of 5 to 25% by weight, 5 to 20% by weight, or 10 to 20% byweight, based upon the total weight of the polyol blend.

Clause 98. The isocyanate-reactive composition of any one of clause 80to clause 97, wherein the aromatic amine-initiated polyether polyol andthe saccharide-initiated polyether polyol are present in a weight ratioof at least 0.8:1, 1:1 to 5:1, 1:1 to 2:1 or 1:1 to 1.5:1.

Clause 99. The isocyanate-reactive composition of any one of clause 80to clause 98, wherein the aromatic amine-initiated polyether polyol andthe aromatic polyester polyol are present in a weight ratio of at least1:1, 1:1 to 5:1, 2:1 to 4:1 or 2.5:1 to 3.5:1.

Clause 100. The isocyanate-reactive composition of any one of clause 80to clause 99, wherein the saccharide-initiated polyether polyol and thearomatic polyester polyol are present in a weight ratio of at least 1:1,1:1 to 5:1, 2:1 to 4:1 or, 2.5:1 to 3.0:1.

Clause 101. The isocyanate-reactive composition of any one of clause 80to clause 100, wherein the polyol blend has a weighted averagefunctionality of 3 to 5, such as 3.5 to 4.5 or 3.8 to 4.2, and/or aweighted average hydroxyl number of 300 to 500 mg KOH/g, such as 350 to450 mg KOH/g.

Clause 102. The isocyanate-reactive composition of any one of clause 80to clause 101, wherein the polyol blend is present in the polyurethanefoam-forming composition in an amount of at least 50% by weight, 50 to90% by weight or 60 to 80% by weight, based on the total weight of theisocyanate-reactive composition.

Clause 103. The isocyanate-reactive composition of any one of clause 80to clause 102, wherein the polyol blend has a content of —C₂H₄O— unitsof 8 to 15% by weight or 8 to 12% by weight, based on total weight ofthe isocyanate-reactive composition.

Clause 104. The isocyanate-reactive composition of any one of clause 80to clause 103, wherein the sum of the amount of the aromaticamine-initiated polyether polyol, the saccharide-initiated polyetherpolyol, and the aromatic polyester polyol is at least 90% by weight, atleast 95% by weight, at least 98% by weight, or 100% by weight, based onthe total weight of the polyol blend.

Clause 105. The isocyanate-reactive composition of any one of clause 80to clause 104, wherein the polyol blend does not include any filledpolyol, such as polymer polyol, PIPA polyol and/or PHD polyol.

Clause 106. The isocyanate-reactive composition of any one of clause 80to clause 105, wherein the HCFO comprises1-chloro-3,3,3-trifluoropropene (HCFO-1233zd, E and/or Z isomer),2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), HCFO1223,1,2-dichloro-1,2-difluoroethene (E and/or Z isomer),3,3-dichloro-3-fluoropropene, 2-chloro-1,1,1,4,4,4-hexafluorobutene-2 (Eand/or Z isomer), 2-chloro-1,1,1,3,4,4,4-heptafluorobutene-2 (E and/or Zisomer.

Clause 107. The isocyanate-reactive composition of any one of clause 80to clause 106, wherein the boiling point, at atmospheric pressure, ofthe HCFO is at least −25° C., at least −20° C., or at least −19° C., and40° C. or less, 35° C. or less, or 33° C. or less, such as where theHCFO has a boiling point, at atmospheric pressure, of −25° C. to 40° C.,−20° C. to 35° C., or −19° C. to 33° C.

Clause 108. The isocyanate-reactive composition of any one of clause 80to clause 107, wherein HCFO is present in an amount of at least 10% byweight, 10 to 30% by weight, 15 to 25% by weight or 18 to 22% by weight,based on the total weight of the isocyanate-reactive composition.

Clause 109. The isocyanate-reactive composition of any one of clause 80to clause 108, wherein HCFO is present in amount of at least 90% byweight, at least 95% by weight, at least 99% by weight or 100% byweight, based on the total weight of the physical blowing agent in theblowing agent composition.

Clause 110. The isocyanate-reactive composition of any one of clause 80to clause 109, wherein the carbon dioxide generating chemical blowingagent comprises water and/or a formate-blocked amine.

Clause 111. The isocyanate-reactive composition of any one of clause 80to clause 110, wherein the carbon dioxide generating chemical blowingagent is present in an amount of 0.5 to 5.0% by weight, 1 to 3% byweight, 1.0 to 2.0% by weight, or 1.2 to 1.8% by weight, based on thetotal weight of the isocyanate-reactive composition.

Clause 112. The isocyanate-reactive composition of any one of clause 80to clause 111, wherein the physical blowing agent composition and thecarbon dioxide generating chemical blowing agent are present in arelative ratio, by weight, of 5:1 to 20:1 or 10:1 to 15:1.

Clause 113. The isocyanate-reactive composition of any one of clause 80to clause 112, wherein the isocyanate-reactive composition comprises asurfactant, such as a polyether-modified polysiloxane.

Clause 114. The isocyanate-reactive composition of any one of clause 80to clause 113, wherein the isocyanate-reactive composition comprises acatalyst, such as a tertiary amine and/or an organometallic, such aswhere the tertiary amine comprises pentamethyldiethylenetriamine,N,N-dimethylcyclohexylamine,N,N′,N″-tris(3-dimethylaminopropyl-)hexahydrotriazine,tetramethylethylenediamine, tetraethylene diamine, benzyldimethylamineor a combination thereof and/or the organometallic catalyst comprisesdibutyltin dilaurate, dibutyltin diacetate, stannous octoate, potassiumoctoate, potassium acetate, potassium 2-ethylhexanoate, or a combinationthereof.

Clause 115. A polyurethane foam comprising a reaction product of theisocyanate-reactive composition of any one of clause 80 to clause 114with a polyisocyanate, wherein the polyurethane foam has a closed-cellcontent of more than 80 percent, more than 85 percent, or more than 88percent, as measured according to ASTM D6226-15.

Clause 116. The polyurethane foam of clause 115, wherein thepolyurethane foam has a thermal conductivity measured at 35° F. (2° C.)of less than 0.126 BTU-in/h-ft2-° F. and measured at 75° F. (24° C.) ofless than 0.140 BTU-in/h-ft2-° F. for foam from the core of 2-inch thickpanels, as measured according to ASTM C518-15.

Clause 117. A composite element comprising the polyurethane foam ofclause 115 or clause 116 sandwiched between one or more facersubstrates, such as where the facer substrate is constructed of plastic,such a polypropylene resin reinforced with continuous bi-directionalglass fibers or a fiberglass reinforced polyester copolymer, paper,wood, or metal.

Clause 118. A refrigeration apparatus, such as a refrigerator, freezer,trailer, or cooler comprising the composite element of clause 117.

The non-limiting and non-exhaustive examples that follow are intended tofurther describe various non-limiting and non-exhaustive implementationswithout restricting the scope of the implementations described in thisspecification.

Examples

Foam-forming compositions were prepared using the ingredients andamounts (in parts by weight) set forth in Table 1. The followingmaterials were used:

POLYOL 1: a polyether polyol having a hydroxyl number of 388 mgKOH/g anda functionality of 4, prepared by alkoxylating o-TDA, in which thealkylene oxide is 37% by weight ethylene oxide and 63% by weightpropylene oxide so that the polyether polyol has a content of —C₂H₄O—units of 29.2% by weight, based on total weight of the polyether polyol;

POLYOL 2: a polyether polyol having a hydroxyl number of 470 mg KOH/gand a functionality of 5.5, prepared by alkoxylating a mixture ofsucrose and water, in which the alkylene oxide is 30% by weight ethyleneoxide and 70% by weight propylene oxide so that the polyether polyol hasa content of —C₂H₄O— units of 20.5% by weight, based on total weight ofthe polyether polyol

POLYOL 3: a polyether polyol having a hydroxyl number of 400 mg KOH/gand a functionality of 4, prepared by alkoxylating o-TDA, in which thealkylene oxide is 100% propylene oxide so that the polyether polyol hasno —C₂H₄O— units;

POLYOL 4: a polyether polyol having a hydroxyl number of 380 mg KOH/gand a functionality of 5.3, prepared by alkoxylating a mixture ofsucrose and water, in which the alkylene oxide is 100% propylene oxideso that the polyether polyol has no —C₂H₄O— units;

POLYOL 5: an aromatic polyester polyol having an OH number of 240 mgKOH/g and a functionality of 2, and a content of —C₂H₄O— units of 44.9%by weight, based on total weight of the aromatic polyester polyol;

SURFACTANT: Dabco® DC5357 from Evonik;

CATALYST 1: N,N,N′,N″,N″-pentamethyldiethylenetriamine, Polycat™ 5 fromEvonik;

CATALYST 2: solution of. potassium-octoate in diethylene glycol, Dabco®K-15 from Evonik;

BLOWING AGENT: trans-1,1,1-trifluoro-3-chloropropene, Solstice® fromHoneywell International Inc.;

ISO 1: polymeric diphenylmethane diisocyanate (pMDI); NCO weight 30.5%;viscosity 350 mPa·s @ 25° C. (MONDUR® 1515 from Covestro);

ISO 2: polymeric diphenylmethane diisocyanate (pMDI); NCO weight 31.5%;viscosity 200 mPa·s @ 25° C. (MONDUR® MR from Covestro).

Foams were prepared using a HK-100 high-pressure foam machine. Theliquid output was maintained at a constant 21° C. for the Resin and 27°C. for the Isocyanate side with an output range of 454 grams/second.Foam was shot into a 79″×8″×2″ (200×20×5 cm) mold between heated platenswith a target overpack of 10% based on minimum fill density. The platenswere maintained at 49° C. The foam remained in the mold and was allowedto cure for 10 minutes at 49° C. before removing. A 8″×8′×1″ section offoam was sampled from the panels and used for k-factor testing accordingto ASTM C518. Lid opening swell was determined by foaming theaforementioned mold at an overpack level of 10% and allowing the part todemold for 2 minutes. After 2 minutes, the lid clamps were removed andthe lid allowed to open based on the degree of foam swelling. The degreeof swelling was measured at 30 seconds, 180 seconds, and 300 secondsafter the lid clamps were removed. Jumbo tool demold was determined byfoaming a 70 cm×40 cm×9 cm closed mold via a shot port at a moldtemperature of 45° C. with an amount of foam to achieve a foam densityof either 2.10 or 2.30 pcf. After the foam was dispensed, the shot portwas closed with a cork and the foam allowed to cure for the specifiedamount of time (2, 3, or 4 minutes). After the specified demold time,the mold lid was opened and the part removed and allowed to restovernight. After 24 hours, the thickness of the part was measured at thecentermost point to determine the degree of foam swelling.

Flow was evaluated as described in U.S. Pat. No. 10,106,641 (at col. 12,lines 22-61, the cited portion of which being incorporated herein byreference). Additionally, a pressure transducer was located 10 cm abovethe protruding sheet metal based edge, which recorded the foamingpressure during the process. The rise rate was derived from the foamheight data as a function of time. Rise rate profiles for selectedexamples are displayed in FIG. 1 . These examples illustrate flowimprovements, particularly early maximum rise rate and general flow,which is currently believed to result in improved cell structure andfoam performance, leading to improved k-factor, i.e., improved thermalinsulation.

Results are set forth in Table 1. Examples 12 and 17-20 are inventiveexamples and Examples 1-11 and 13-16 are comparative examples.

TABLE 1 Component Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Ex. 9Ex. 10 POLYOL 1 31.36 31.36 31.43 31.43 31.78 31.83 31.93 32.01 32.0132.45 POLYOL 2 27.80 27.80 27.94 27.94 28.24 28.28 28.37 — — — POLYOL 3— — — — — — — POLYOL 4 — — — — — — — 21.42 21.42 21.72 POLYOL 5 10.4110.41 10.48 10.48 10.59 10.60 10.63 17.78 17.78 18.03 SURFACTANT 2.862.86 2.9 2.9 2.90 2.90 2.90 2.9 2.9 2.90 CATALYST 1 0.87 0.87 0.87 0.870.87 0.87 0.87 0.9 0.9 0.90 CATALYST 2 0.87 0.87 0.87 0.87 0.87 0.870.80 0.9 0.9 0.90 Water 1.38 1.38 1.75 1.75 1.70 1.60 1.45 1.88 1.881.80 BLOWING AGENT 24.45 24.45 23.76 23.76 23.05 23.05 23.03 22.21 22.2121.30 ISO ISO 1 ISO 2 ISO 1 ISO 2 ISO 2 ISO 2 ISO 2 ISO 1 ISO 2 ISO 2INDEX 1.30 1.34 1.30 1.34 1.34 1.46 1.40 1.26 1.30 1.34 —C₂H₄O— units infoam- 9.0 9.0 8.7 8.7 8.8 8.8 8.8 8.1 8.1 8.1 forming composition¹Overall HCFO Content (%) 11.3 11.3 10.6 10.6 10.2 10.2 10.2 10.4 10.410.0 RESULTS Cream Time (sec) Froth Froth Froth Froth Froth Froth FrothFroth Froth Froth Gel Time (sec) 37 37 37 36 38 33 35 36 35 35 Free-RiseDensity (pcf) 1.38 1.42 1.25 1.30 1.26 1.37 1.34 1.21 1.17 1.21 BoschMin. Fill Density 2.05 1.99 1.93 1.93 1.97 1.93 2.02 1.86 1.88 1.90(pcf) Packed Density 2.25 2.18 2.12 2.13 2.18 2.12 2.22 2.05 2.07 2.11(10%, pcf) Core Density (pcf) 1.92 1.88 1.85 1.83 1.88 1.84 1.94 1.781.73 1.83 Overall vs Core Density 1.17 1.16 1.15 1.16 1.16 1.15 1.141.15 1.20 1.15 Ratio Closed Cell Content (%) 91.3 90.6 91.0 90.5 90.490.5 91.0 89.7 91.3 91.5 K-factor @35° F. 0.117 0.116 0.116 0.118 0.1180.118 0.116 0.115 0.122 0.118 (((BTU*in)/(h*ft2*° F.)) K-factor @75° F.0.131 0.131 0.131 0.133 0.134 0.134 0.132 0.131 0.137 0.134(((BTU*in)/(h*ft2*° F.)) Compressive Strength+ 20.6 18.9 18.6 18.5 19.818.9 20.9 18.1 17.2 18.4 (psi) Compressive Strength= 35.0 31.2 34.7 32.734.9 34.8 36.1 32.6 30.2 31.3 (psi) Dimensional Stability −30° 0.0 −0.2−0.1 −0.1 −0.1 N/A² −0.2 −0.1 0.0 0.1 C. @ 1 day (%) DimensionalStability −30° 0.2 −0.1 −0.4 0.0 −0.3 0.2 −0.2 0.1 0.0 0.1 C. @ 7 days(%) Dimensional Stability 70° −1.3 −1.1 −1.4 −1.2 −1.0 N/A  −1.7 −1.0−0.8 −0.9 C. @ 1 day (%) Dimensional Stability 70° −0.5 −0.4 −0.6 −0.6−0.9 0.3 −1.4 −0.4 −0.3 −0.8 C. @ 7 days (%) Lid Opening @ 0.5 min 0.2210.231 0.127 0.141 0.189 0.153 0.094 0.084 0.072 0.237 (in); 10% OP LidOpening @ 3 min 0.117 0.223 0.117 0.129 0.174 0.136 0.091 0.079 0.0630.223 (in); 10% OP Lid Opening @ 5 min 0.113 0.212 0.110 0.121 0.1600.127 0.083 0.075 0.051 0.214 (in); 10% OP Jumbo Tool: 2.10 pcf @ 7.16.3 9.8 10.6 7.0 4.7 7.9 N/A³ N/A³ 15.9 2 min (mm) Jumbo Tool: 2.10 pcf@ 4.5 3.1 7.4 8.1 6.1 3.0 7.2 14.0 16.1 12.0 3 min (mm) Jumbo Tool: 2.10pcf @ 3.3 3.2 3.7 5.3 4.3 1.8 5.6 9.7 9.1 8.8 4 min (mm) Jumbo Tool:2.30 pcf @ 13.4 7.5 13.6 12.9 12.5 13.2 11.5 25.6 24.1 19.3 2 min (mm)Jumbo Tool: 2.30 pcf @ 7.4 5.5 10.1 8.0 8.7 10.1 7.3 18.9 N/A³ 16.3 3min (mm) Jumbo Tool: 2.30 pcf @ 8.1 6.5 7.6 5.9 5.4 8.3 3.0 14.1 14.810.1 4 min (mm) Flow Max Pressure (hPa) 126 124 138 — — — 145 132 128103 Final Height (cm) 112 113 115 — — — 99 116 114 107 Max Rise Time (s)28 24 28 — — — 27 23 23 23 Max Rise Rate (cm/s) 2.6 2.7 2.6 — — — 2.53.2 3.3 3.3 Component Ex. 11 Ex. 12 Ex. 13 Ex. 14 Ex. 15 Ex. 16 Ex. 17Ex. 18 Ex. 19 Ex. 20 POLYOL 1 32.48 — 39.00 — — — — — — — POLYOL 2 —29.02 32.65 29.02 — — 29.66 29.93 29.75 30.10 POLYOL 3 — 31.95 — 31.9531.95 31.95 32.65 32.90 32.70 32.94 POLYOL 4 21.74 — — — 29.02 24.65 — —— — POLYOL 5 18.04 10.63 — 10.63 10.63 15.00 10.86 10.80 10.73 11.01SURFACTANT 2.90 2.90 2.90 2.90 2.90 2.90 2.90 2.50 2.90 2.90 CATALYST 10.87 0.90 0.90 0.90 0.90 0.90 0.85 0.80 0.85 0.85 CATALYST 2 0.87 0.800.75 0.80 0.80 0.80 0.76 0.55 0.55 0.55 Water 1.80 1.60 1.60 1.80 1.601.60 1.52 1.52 1.52 1.65 BLOWING AGENT 21.30 22.20 22.20 22.00 22.2022.20 21.00 21.00 21.00 20.00 ISO ISO 2 ISO 2 ISO 2 ISO 2 ISO 2 ISO 2ISO 2 ISO 2 ISO 2 ISO 2 INDEX 1.45 1.36 1.31 1.40 1.30 1.48 1.22 1.221.22 1.18 —C₂H₄O— units in foam- 7.7 4.7 8.0 4.6 2.1 3.0 5.1 5.1 5.1 5.2forming composition¹ Overall HCFO Content (%) 9.4 9.8 9.8 9.4 9.8 9.89.8 9.8 9.8 9.4 RESULTS Cream Time (sec) Froth Froth Froth Froth FrothFroth Froth Froth Froth Froth Gel Time (sec) 34 32 36 31 34 34 30 34 3133 Free-Rise Density (pcf) 1.20 1.30 1.38 1.31 1.43 1.25 1.38 1.37 1.491.43 Bosch Min. Fill Density 2.00 2.06 2.08 2.00 2.08 1.98 2.05 2.052.04 2.03 (pcf) Packed Density 2.19 2.26 2.28 2.22 2.29 2.19 2.28 2.262.25 2.26 (10%, pcf) Core Density (pcf) 1.88 1.96 1.97 1.94 1.96 1.922.04 2.01 2.01 2.04 Overall vs Core Density 1.16 1.15 1.16 1.14 1.171.14 1.12 1.12 1.12 1.11 Ratio Closed Cell Content (%) 89.3 89.5 89.090.2 90.7 89.8 90.9 90.5 90.4 90.8 K-factor @35° F. 0.118 0.115 0.1180.118 0.117 0.118 0.114 0.116 0.115 0.113 (((BTU*in)/(h*ft2*° F.))K-factor @75° F. 0.133 0.130 0.134 0.134 0.133 0.135 0.129 0.131 0.1310.129 (((BTU*in)/(h*ft2*° F.)) Compressive Strength+ 19.7 20.5 19.5 18.720.5 18.6 22.7 21.9 21.8 22.7 (psi) Compressive Strength= 33.2 37.8 36.139.4 35.5 33.8 41.0 39.4 38.9 38.2 (psi) Dimensional Stability −30° −0.10.2 0.3 −0.2 −0.3 −0.3 −0.2 −0.3 0.0 0.1 C. @ 1 day (%) DimensionalStability −30° 0.1 −0.1 0.0 0.1 0.0 −0.5 0.2 −0.1 0.1 0.1 C. @ 7 days(%) Dimensional Stability 70° −1.4 −1.2 −1.4 −1.8 −2.2 −2.0 −1.5 −1.4−1.3 −1.0 C. @ 1 day (%) Dimensional Stability 70° −1.0 −1.0 −0.6 −1.5−1.0 −1.1 −0.9 −1.1 −0.5 −0.9 C. @ 7 days (%) Lid Opening @ 0.5 min0.267 0.063 0.050 0.058 0.101 0.135 0.096 0.104 0.085 0.057 (in); 10% OPLid Opening @ 3 min 0.250 0.055 0.043 0.052 0.088 0.123 0.089 0.0950.075 0.049 (in); 10% OP Lid Opening @ 5 min 0.236 0.048 0.039 0.0460.079 0.115 0.083 0.085 0.069 0.040 (in); 10% OP Jumbo Tool: 2.10 pcf @12.2 7.3 4.5 10.2 10.2 8.8 9.5 9.2 9.2 9.3 2 min (mm) Jumbo Tool: 2.10pcf @ 8.8 5.8 2.9 8.0 8.0 7.0 8.1 7.8 9.0 8.5 3 min (mm) Jumbo Tool:2.10 pcf @ 6.5 5.0 1.9 8.0 8.0 6.1 8.4 7.2 8.8 8.0 4 min (mm) JumboTool: 2.30 pcf @ 15.5 5.1 5.6 12.0 12.0 9.3 10.0 9.4 10.5 10.1 2 min(mm) Jumbo Tool: 2.30 pcf @ 11.3 3.5 3.9 9.5 9.5 8.1 8.9 8.0 9.1 9.5 3min (mm) Jumbo Tool: 2.30 pcf @ 6.3 2.8 2.7 8.8 8.8 7.9 8.2 8.2 8.9 8.14 min (mm) Flow Max Pressure (hPa) 71 101 166 62 84 84 171 141 170 157Final Height (cm) 106 92 101 102 107 103 103 104 102 102 Max Rise Time(s) 27 23 28 17 16 15 20 23 18 19 Max Rise Rate (cm/s) 2.5 2.7 2.3 2.93.4 3.3 3.1 2.8 3.1 3.1 ¹Reported value is based on total weight of thefoam-forming composition ²Equipment failure led to missing results³Could not measure sample due to foam cracking

Although the invention has been described in detail in the foregoing forthe purpose of illustration, it is to be understood that such detail issolely for that purpose and that variations can be made therein by thoseskilled in the art without departing from the spirit and scope of theinvention except as it may be limited by the claims.

What is claimed is:
 1. A polyurethane foam-forming compositioncomprising: (a) a polyol blend comprising: (1) at least 30% by weight,based on total weight of the polyol blend, of an aromaticamine-initiated polyether polyol having a functionality of at least 2.5and an OH number of 200 to 600 mg KOH/g; (2) at least 30% by weight,based on total weight of the polyol blend, of a saccharide-initiatedpolyether polyol having a functionality of 4 to 6 and an OH number of200 to 600 g/KOH gram; and (3) 1 to 25% by weight, based on total weightof the polyol blend, of an aromatic polyester polyol having afunctionality of 1.5 to 3 and an OH number of 150 to 410 mg KOH/g,wherein the polyol blend has a content of —C₂H₄O— units of 3 to 6% byweight, based on the total weight of the polyurethane foam-formingcomposition; (b) a blowing agent composition comprising: (1) a physicalblowing agent and (2) a carbon dioxide-generating chemical blowingagent, wherein: (i) the physical blowing agent comprises ahydrochlorofluoroolefin that is present in an amount of 5% to 15% byweight, based on total weight of the polyurethane foam-formingcomposition, and in an amount of at least 80% by weight, based on totalweight of physical blowing agent in the blowing agent composition, and(ii) the physical blowing agent composition and the carbon dioxidegenerating chemical blowing agent are present in a relative ratio, byweight, of 5:1 to 50:1; and (c) a polyisocyanate present in an amountsufficient to provide an isocyanate index of 1.15 to less than 1.40. 2.The polyurethane foam-forming composition of claim 1, wherein thearomatic amine-initiated polyether polyol has a content of —C₂H₄O— unitsof less than 10% by weight, based on total weight of the aromaticamine-initiated polyether polyol.
 3. The polyurethane foam-formingcomposition of claim 1, wherein the aromatic amine-initiated polyetherpolyol has a content of —C₂H₄O— units of less than 2% by weight, basedon total weight of the aromatic amine-initiated polyether polyol.
 4. Thepolyurethane foam-forming composition of claim 1, wherein the aromaticamine-initiated polyether polyol is present in an amount of 30 to 60% byweight, based on the total weight of the polyol blend.
 5. Thepolyurethane foam-forming composition of claim 1, wherein thesaccharide-initiated polyether polyol has a content of —C₂H₄O— units ofless than 40% by weight, based on total weight of thesaccharide-initiated polyether polyol.
 6. The polyurethane foam-formingcomposition of claim 4, wherein the saccharide-initiated polyol ispresent in an amount of 30 to 60% by weight.
 7. The polyurethanefoam-forming composition of claim 6, wherein the aromatic polyesterpolyol is present in an amount of 5 to 25% by weight, based upon thetotal weight of the polyol blend.
 8. The polyurethane foam-formingcomposition of claim 1, wherein the aromatic amine-initiated polyetherpolyol and the saccharide-initiated polyether polyol are present in aweight ratio of 1:1 to 5:1, the aromatic amine-initiated polyetherpolyol and the aromatic polyester polyol are present in a weight ratioof 1:1 to 5:1, and the saccharide-initiated polyether polyol and thearomatic polyester polyol are present in a weight ratio of 1:1 to 5:1.9. The polyurethane foam-forming composition of claim 1, wherein thepolyol blend has a content of —C₂H₄O— units of 4 to 6% by weight, basedon total weight of the polyurethane foam-forming composition.
 10. Thepolyurethane foam-forming composition of claim 1, wherein the polyolblend does not include a filled polyol.
 11. The polyurethanefoam-forming composition of claim 1, wherein the sum of the amount ofthe aromatic amine-initiated polyether polyol, the saccharide-initiatedpolyether polyol, and the aromatic polyester polyol is at least 90% byweight, based on the total weight of the polyol blend.
 12. Thepolyurethane foam-forming composition of claim 1, whereinhydrochlorofluoroolefin is present in amount of at least 90% by weight,based on the total weight of the physical blowing agent in the blowingagent composition.
 13. The polyurethane foam-forming composition ofclaim 12, wherein the physical blowing agent composition and the carbondioxide generating chemical blowing agent are present in a relativeratio, by weight, of 5:1 to 20:1.
 14. A polyurethane foam produced fromthe polyurethane foam-forming composition of claim
 1. 15. A method ofproducing a polyurethane foam, comprising reacting, at an isocyanateindex of 1.15 to less than 1.40, a polyurethane foam-forming compositioncomprising a polyol blend, a polyisocyanate, and a blowing agentcomposition, wherein: (a) the polyol blend comprises (1) at least 30% byweight, based on total weight of the polyol blend, of an aromaticamine-initiated polyether polyol having a functionality of at least 2.5and an OH number of 200 to 600 mg KOH/g; (2) at least 30% by weight,based on total weight of the polyol blend, of a saccharide-initiatedpolyether polyol having a functionality of 4 to 6 and an OH number of200 to 600 g/KOH gram; and (3) 1 to 25% by weight, based on total weightof the polyol blend, of an aromatic polyester polyol having afunctionality of 1.5 to 3 and an OH number of 150 to 410 mg KOH/g,wherein the polyol blend has a content of —C₂H₄O— units of 3 to 6% byweight, based on the total weight of the polyurethane foam-formingcomposition; (b) the blowing agent composition comprises: (1) a physicalblowing agent and (2) a carbon dioxide-generating chemical blowingagent, wherein: (i) the physical blowing agent comprises ahydrochlorofluoroolefin that is present in an amount of 5% to 15% byweight, based on total weight of the polyurethane foam-formingcomposition and in an amount of at least 80% by weight, based on totalweight of physical blowing agent in the blowing agent composition, and(ii) the physical blowing agent composition and the carbon dioxidegenerating chemical blowing agent are present in a relative ratio, byweight, of 5:1 to 50:1.
 16. The method of claim 15, wherein the aromaticamine-initiated polyether polyol has a content of —C₂H₄O— units of lessthan 2% by weight, based on total weight of the aromatic amine-initiatedpolyether polyol.
 17. The method of claim 15, wherein the aromaticamine-initiated polyether polyol is present in an amount of 30 to 60% byweight, based on the total weight of the polyol blend, thesaccharide-initiated polyol is present in an amount of 30 to 60% byweight, and the aromatic polyester polyol is present in an amount of 5to 25% by weight, based upon the total weight of the polyol blend. 18.The method of claim 15, wherein the sum of the amount of the aromaticamine-initiated polyether polyol, the saccharide-initiated polyetherpolyol, and the aromatic polyester polyol is at least 90% by weight,based on the total weight of the polyol blend.
 19. Anisocyanate-reactive composition, comprising: (a) polyol blendcomprising: (1) at least 30% by weight, based on total weight of thepolyol blend, of an aromatic amine-initiated polyether polyol having afunctionality of at least 2.5 and an OH number of 200 to 600 mg KOH/g;(2) at least 30% by weight, based on total weight of the polyol blend,of a saccharide-initiated polyether polyol having a functionality of 4to 6 and an OH number of 200 to 600 g/KOH gram; and (3) 1 to 25% byweight, based on total weight of the polyol blend, of an aromaticpolyester polyol having a functionality of 1.5 to 3 and an OH number of150 to 410 mg KOH/g, wherein the polyol blend has a content of —C₂H₄O—units of 5 to 15% by weight, based on the total weight of theisocyanate-reactive composition; and (b) a blowing agent compositioncomprising: (1) a physical blowing agent and (2) a carbondioxide-generating chemical blowing agent, wherein: (i) the physicalblowing agent comprises a hydrochlorofluoroolefin that is present in anamount of 10% to 30% by weight, based on total weight of theisocyanate-reactive composition and in an amount of at least 80% byweight, based on total weight of physical blowing agent in the blowingagent composition, and (ii) the physical blowing agent composition andthe carbon dioxide generating chemical blowing agent are present in arelative ratio, by weight, of 5:1 to 50:1.
 20. The isocyanate-reactivecomposition of claim 19, wherein the aromatic amine-initiated polyetherpolyol is present in an amount of 30 to 60% by weight, based on thetotal weight of the polyol blend, the saccharide-initiated polyol ispresent in an amount of 30 to 60% by weight, the aromatic polyesterpolyol is present in an amount of 5 to 25% by weight, based upon thetotal weight of the polyol blend, and the sum of the amount of thearomatic amine-initiated polyether polyol, the saccharide-initiatedpolyether polyol, and the aromatic polyester polyol is at least 90% byweight, based on the total weight of the polyol blend.